An exhibition at the Australian National Maritime Museum in Sydney features unusual images captured with a digital radiographic machine and arranged in an evolutionary sequence. Smithsonian National Museum of Natural History fish curator Sandra Raredon captured the images of thousands of fish specimens. All up, the institution, in Washington DC, has four million individual specimens representing 70 per cent of total fish diversity. The X-rays allow scientists to document internal features without ruining specimens, but they also make for unusual abstract artworks. The exhibition will be open until February 2016.